Magnitude 7.9 earthquake: Midnight shaking and confusion in an Alaskan Cabin

By Lester Lubetkin, retired from US Forest Service

Check your hazard rank

 

I was lying in bed, doing some late night reading, when the bed started to rock. Then the walls in the two story log home made themselves known and started “creaking” Wwhhat? Oh! Another earthquake!

 

The earth awakens

That was the start of the shaking from the recent M7.9 Alaska event. It was shortly after midnight on January 23; it had been lightly snowing earlier and the skies were cloudy and starless. Alice, my wife, was downstairs and yelled out “I think this is another earthquake” just as I was coming to the same conclusion. It’s amazing how long it can take to realize the obvious. In big windstorms, we have come to learn, the log cabin will suddenly let out a loud “crack” or “growl” as one log shifts against another. But this was very different – sustained, with lots of movement of the floor, not just noise.

After a few moments, the shaking was not subsiding, and I realized that I should move from the upstairs loft down to the main floor. The house continued to creak and groan, and the ground continued to gently sway and rock, while a hanging decorative ball swung strongly back and forth. This was really a long one!

 

Why isn’t ‘Drop, Cover and Hold On’ part of our muscle memory?

But it was the anticipation that was the worst. That sense, as the tremors continued, that this must be a very large earthquake, and that the shaking could get violent. What should we do, where should we be standing, are we going to be OK? Alice and I hugged, said we loved each other, then moved to near a doorway. That is when Alice said, “No wait- I don’t think we’re supposed to do that anymore- I think we’re supposed to lie near a couch or table or something”. We had both graduated with geology college degrees, and still didn’t really know what to do. I was still in the old school thinking of get to a doorway.

 

The Surface Waves arrive

So, Alice went to her spot and I went to mine, standing next to the front door with these massive log beams directly over my head., But I kept thinking about the fatalities from the Guatemalan and Mexico City earthquakes, where the walls collapsed outward, and the large roof beams fell inward. So, I was ready to move to the couch if the shaking got stronger. The shaking just kept going, gently lifting us and then releasing us. Not the sharp jolts I kept expecting to feel, and for a very long minute and a half. And then, the house started to settle, though there was still a slow, nearly imperceptible swaying motion, giving us the feeling of being in a boat. I couldn’t feel it at first, but Alice, who was seated on the floor was well aware of the presence of these long “surface waves”. And she was always first with sensing the small aftershocks that followed- “here comes another one!” But the violent sequel we were worried about fortunately never came.

I remembered the stories from the 1906 San Francisco Earthquake, and how so much of the damage was from the broken gas lines and subsequent fires. As soon as the shaking had quit, I went downstairs to see that the fuel line to the heater was intact, that the water lines were OK. All seemed in order.

 

Tsunami Warning by Loudspeaker

And then, we heard the faint sounds of sirens outside and the muffled words of a loudspeaker. As the sirens got louder, we opened the door to better hear the message. Though coming from a few miles away, we could hear it clearly: “Evacuate Immediately to higher ground, Tsunami Warning, if you are in a low lying area, Evacuate Immediately” over and over.

We are up on a bluff, a good 1,000 feet (300 m) above the sea level town of Homer, Alaska. Yet we still froze for a moment, wondering, do we need to flee? But then we realized we are the higher ground others would rush to. I can’t imagine hearing that message at 12:30 am in the morning, the outside temperature about 15° F (-9°C) with a chance of snow, and realizing you need to rush out the door to avoid an approaching tidal wave!

Since we had not lost power during the earthquake, off we went to the computer to find out what we could about the earthquake – its location, size, predictions, etc. At the top of the US Geological Survey web page was a red banner warning us of the threat of a tsunami. Our cell phone had already pushed a notification to us the same thing. Even though no tsunami ever came, it was comforting to know the Pacific Tsunami Warning Center was not taking chances on people falling through the cracks.

 

The USGS website was up even when the government was down

According to the USGS website (which was fortunately still up and current despite the US federal government shutdown), the earthquake was reported as being Magnitude 8, located about 170 miles (275 km) east-southeast of Kodiak, Alaska.

We were surprised it wasn’t closer. Our town of Homer, Alaska sits on Kachemak Bay near the southern end of the Cook Inlet. Homer is about 100 miles northeast from Kodiak. By comparison, we were only 150 miles (240 km) southeast from the epicenter of the devastating 1964 M=9.2 ‘Good Friday’ Alaska earthquake.

 

We were not the only ones shaken

But maybe the strangest part of the evening followed the main shaking. A very small gray-bellied bird, a Brown Creeper, suddenly appeared just outside our window while the rolling aftershocks continued. It sat there perfectly still, but occasionally flew at the window, as if trying to get in. It stayed there silent in the cold for a full 15 or 20 minutes. This is not a nocturnal bird, and we have not seen a Brown Creeper at the house for several months. Where it came from and what it was trying to accomplish we will never know, but we suspect that it, too, had been shaken.